This invention relates generally to web splicing and, more particularly, to the splicing of the leading end portion of a fresh roll of web to the trailing end portion of a running web traveling through a continuous web processing line such as a printing press or the like. The invention is applicable both to systems in which the splice is made on the fly and to systems in which the splice is made while the running web is stationary.
A web processing system with a flying splicer is disclosed in Keene et al U.S. Pat. No. 4,564,150. In the system disclosed in that patent, the free end of the web of the fresh roll is cut into a V shape and a V-shaped band of adhesive is applied to the free end portion of the web. An adhesive tab also is applied to the free end portion of the web at the apex of the V and secures the outer layer of the roll to the adjacent inner layer. The tab holds the outer layer against the inner layer while the roll is being rotated preparatory to splicing and then tears away as the splice is made.
A system of the type disclosed in the Keene et al patent has two significant drawbacks. First, most of the free edge of the web of the fresh roll is exposed and thus windage which occurs during high speed rotation of the roll tends to unwind the web from the roll and may tear the web. The problem of windage is accentuated by the fact that the exposed leading edge of the roll is V-shaped and thus is relatively long and susceptible to lifting.
The second drawback involves the time required by an operator to place an adhesive splicing pattern on the leading end portion of each roll. Typically, the pattern is applied at the splicing station itself, thereby requiring an operator at each machine.